Referring now to FIGS. 4 through 7, a conventional art is described below. As shown in FIGS. 6 and 7, such parts being dealt by any of parts-supply control apparatuses substantially comprise projection nuts. FIG. 6 illustrates a circular nut, where the reference numeral 1 designates the whole aspect of a circular nut which comprises a main body 2, a tapped hole 3, a flange 4, and a plurality of projections 5 which are formed below the flange 4 and available for fusion. FIG. 4 illustrates a conventional apparatus which deals with such circular nuts shown in FIG. 6 for example. A parts-supply tube 7 having rectangular section and forming a parts-passage 6 and a guide tube 9 of a supply rod 8 are welded together in the orthogonal state. A temporary holding chamber 10 is disposed in the orthogonal domain. An end of the parts-supply tube 7 has such a shape as shown in FIG. 5. Concretely, plates above and below the parts-supply tube 7 are eliminated, whereas a pair of projective pieces 11 and 11 are formed on both sides, and yet, a stopper plate 12 is secured to the front edge of these projective pieces 11 and 11. Therefore, an outlet aperture 13 is formed as shown in FIG. 4. A magnet (a permanent magnet) 14 is secured to the stopper plate 12, where the magnet 14 attracts the nut 1 close to the left end of the parts-passage 6 so that it can be placed in the temporary holding chamber 10, where the nut 1 is provisionally held in the state coaxial with the supply rod 8 as shown in FIG. 4.
The supply rod 8 comprises a large-diametric domain 15 and a guide member 16 having diameter less than that of the large-diametric domain 15. An extrusive surface 17 is formed at the interface of both domains.
FIG. 4 illustrates a nut 1 which is obliquely placed in the parts-passage 6. Assuming that the obliquely placed nut 1 is not present in the parts-passage 6, operation of the above conventional apparatus is described below. When the supply rod 8 is driven forward by a pneumatic cylinder (not shown), the guide member 16 penetrates the tapped hole 3 to cause the extrusive surface 17 to hit against the top surface of the nut 1 before extruding the nut 1 by overcoming the attractive force of the magnet 14. The extruding velocity is predetermined to be faster than the falling velocity of the nut 1 itself.
Nevertheless, whenever operating the above conventional apparatus, as shown in FIG. 4, since the second nut projects itself out of the outlet aperture 13, the flange of the second nut comes into engagement with the preceding nut in the temporary holding chamber 10 in the state obliquely being held below the flange of the preceding nut. In consequence, when the supply rod 8 thrusts itself, the nut in the temporary holding chamber 10 is locked to obstruct execution of smooth delivery of the preceding nut. The same problem also occurs whenever dealing with a square projection nut having four fusible projections in four corners as shown in FIG. 7. The same problem also occurs even when dealing with flatly shaped parts.